Electrical machine.



F.LJUNGSTRUM.

' v ELECTRICAL MACHINE.

' I Patented July 20, 1915.

onrrED STATES PATENT OFFICE.

EE DE-IK LJUNGs'rRoM, or EINsPANG, SWEDEN, AssIe oE 'ro KTIEBOEAGET LJUNGsTR-oMs ANGTUREIN, or FINSPANG, SWEDEN.

ELECTRICAL MACHINE.

Specification of Iietters Patent.

Patented July 20, 1915.

Z?) all whom it may concern Be it knownthat I, FREDRIK LJUNGSTR6M,- a subject of the King of Sweden, and a citizen of Sweden, residing at Finspang, 1n the Kingdom of Sweden, have invented certain new and useful Improvements in or Relating to Electrical Machines, of which the following is a specification.

It has been-proposed before to attach the windings in electrical machines by providing them with dove-tailed projections or the like, cooperating with notches formed in a corresponding manner in the rotatable body,

' a way as to prevent a mutual displacement in any radial direction with regard-to the center of the rotating body but to allow the displacement longitudinally of the winding.

The invention is an improvement on the construction shown in my Patent #1,115,- 220, though available for use with magnets differing in some respects therefrom and is illustrated in the annexed drawings in a 7 construction having dove-tailed parts ]O1Iling the winding and the armature body.

Figure 1 represents a cross section of apart of the rotating body and a part of the winding thereon, the said parts embodying my invention; Fig. 2' represents on a larger scale a similar view of a modified construction of the same omitting the insulation and metal surfaces; and Fig. 3 represents a still further enlarged portion of Fig. 2, showing also the insulation and metal faces.

In Fig. 1 a is the winding and a are the projections attached thereto and entering the notches between the projections b of the rotatable body 6. The projections a and b are provided with step form smaller projections constructed according to the present invention to allow the surfaces 0 and d placed in the longitudinal dlrectlon of the winding at right angles to the longitudinal axes of the projections a b to rest against each other, while the surfaoes e and f donot abut against each other. It is ev dent that hereby a free dilatation of the w nd ng can take place longitudinally of the windlng, avoiding detrimental strains. Between the surfaces cand d the necessary insulating layer g is'put "int Fig. 3),. consistmg for instance of paper, mica, pressboard or the like. In order to strengthen this layer, two metal covers h and i are laid in joined to b and a respectively. During unequal expansion of the winding and the rotating body in the direction of the length of said winding the covers it and a slide over each other. In order to facilitate this slidlng these two metal covers may consist of difi'erent metals as for. instance, iron and brass.

k is. an air-layer between f and e.

In the case of the surfacesc being quite even and smooth the covers it can beomitted.

It is evident that the projections a and b may be shaped in any manner; it is essential, however, that the shape should allow winding in the direction corresponding to the faces d and e of. the steps.

- .VVhat I claim is 1. In an electrical machine, the combination of a rotatable body with a winding thereon, these two parts being provided with alternately arranged projections having parts which engage in a radial direction with respect to said body, but which are adapted to allow displacement in the longitudinal direction of the winding.

2. In an electrical machine, the combination of a rotatable body with a winding thereon, these two parts being provided with projections which have smaller step-form projections on their proximate sides, the latter projections having faces which extend in the longitudinal direction of thewinding, as well as other faces which extend in other directions, the former faces of the proximate step-form projections of the said body and of the winding being adapted to rest upon and slide over each other.

3. In an electrical machine, the combination of a rotatable body with a winding thereon, these two parts being provided with projections which have smaller stepform projections on their proximate sides,

4:. In an 'electricalmachine, the combination of -a rotatable body and a winding sides, with an interposed insulating layer and interposed metallic covers, saidstepiormprojections having faces which extend in the longitudinal direction of the Winding and inclined faces with a space left between each -opposed, pair of faces, of the covers on the fOI1I1er'=TfaC6S being adapted to slip over each other.

tion of a rotatable body and a winding thereon, with an interposed insulating layer and metal covers, the said body and-Wind ing being provided. with a1ternately arranged projections having step-form projections' on their sides,,which are constructed with faces that extend in the longitudinal direction of the winding and with additional faces adaptedand arranged to permit a displacement of said partsby expansion in the longitudinal direction of the Winding, the said metal'coyers fitting on said step form projections and slidin over each other Where they fit on the ormer faces.

' In testimony whereof I have afiixed my signature in presence of two Witnesses; 5, In an electrical machine, the comb1na-' p v FREDRIK LJ GsTRGMQ Witnesses: i I v OSCAR ENes'rRoM,

GoRANsLoY. 

